We need to understand more about how the fetal brain develops for two main reasons. Firstly, abnormalities arising in early development are common and disorders of brain development affect many babies, often with severe consequences for their health and quality of life. Secondly, as humans we have unique or especially highly developed cognitive abilities (such as language), which cannot readily be studied in animal models. Contributing to these two goals is highly consistent with the mission statements of the NICHD and NIMH as they relate to understanding the development and function of the human brain. The informatics part of the project would contribute to the mission of the NIBIB to advance imaging and related technologies. Genes, and the protein products they make, drive development. If we are to understand how the brain is formed, we need to know when genes are switched on (expressed) in early development and in which cells of the brain. Identifying brain structures early in development is a difficult task, partly because structures may have very different sizes, shapes and even relative positions compared to their adult counterparts. The complex three-dimensional (3-D) structure, which also changes during development, adds to the difficulties. The general aim of our project, therefore, is to make an electronic atlas of the developing human brain (EADHB) which will capture expert knowledge to identify brain structures at different stages in digital, interactive 3-D models. These models will also be used for storing, sharing and analyzing the data on where and when genes are expressed in the developing brain. The gene expression data are best understood by relating them to the underlying anatomy and structure of the developing brain. The EADHB will, therefore, have two main components: 1) an electronic (2D and 3D) atlas of the anatomy and form of the developing brain- this will be useful as a teaching and learning tool to help in understanding human developmental brain anatomy, as well as providing a canvas onto which the information on where genes are expressed can be painted. 2) a gene expression database which will allow us to map in 2D and in 3D where genes are expressed in the brain and to relate this to the 2D and 3D anatomy of the brain. In our previous work we have been able to demonstrate on a small scale that we can accomplish this task. Because of the importance in relating the gene expression data to the anatomy of the brain, we are now proposing to collaborate with a world-leading expert in developmental brain anatomy, Professor Luis Puelles. In this new phase of our work we will make every effort to ensure that our brain atlas is readily accessible and linked to other electronic atlases for other species and other organ systems. The EADHB will provide a unique resource to neurobiologists, clinical scientists and educators.